4H-SiC p(+)-n(+) Zener diodes with a breakdown at voltage of 22 V have been fabricated and characterized in continuous and pulsed mode of operation at ambient temperatures of up to 200degreesC. The diodes were capable of operating at dc current densities up to 8 kA/cm(2) and pulsed current densities up to 100 kA/cm(2). They exhibited a value of isothermal dynamic impedance of less than 2.5 Omega at 200degreesC, a zero bias capacitance of 28 pF and mixed avalanche-tunnel breakdown with a positive temperature coefficient of breakdown voltage of about (8-10)(.)10(-5)K(-1).